In buildings, campus facilities and in other public spaces, there exist structurally-related or furniture-related trip hazards or danger points which can lead to accidents and personal injury. These sites are signaled, if at all, with signs and/or warning colors. For example: colored strips on stair treads or indicative texts such as “Caution Step”. In public spaces, for example, for people with impaired vision, signal sounds are used at traffic light installations.
Increasingly, the use of smartphones or other communication devices in street traffic can lead to inattentiveness and thereby to accidents. Thus in some cities, there exist pilot projects with pavement traffic lights or LED lights along the curb, which flash at a pedestrian crossing when a set of pedestrian crossing lights switches to red or if a tram is approaching. These pilot projects have previously been only sporadically implemented and they also require complex infrastructure measures for their implementation.